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Reliability analysis of multimodal scene matching based on correlation peaks

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Chinese Journal of Aeronautics 2024年第9期37卷 433-447页

作者： Zhirui yu Bai ZHU Zhiqiang han yuanxin YE Faculty of Geosciences and Engineering Southwest Jiaotong UniversityChengdu 611756China

The navigation system plays a pivotal role in guiding aircraft along designated routes,ensuring precise and punctual arrival at *** integration of scene matching with an inertial navigation system enhances the capability of providing a dependable guarantee for success-ful accomplishment of flight ***,assuring reliability in scene matching encoun-ters significant challenges in areas characterized by repetitive or weak *** tackle these challenges,we propose a novel method to assess the reliability of scene matching based on the dis-tinctive characteristics of correlation *** proposed method leverages the fact that the sim-ilarity of the optimal matching result is significantly higher than that of the surrounding area,and three novel indicators(e.g.,relative height,slope of a correlation peak,and ratio of a sub peak to the main peak)are determined to conjointly evaluate the reliability of scene *** pro-posed method entails matching a real-time image with a reference image to generate a correlation surface.A correlation peak is then obtained by extracting the portion of the correlation surface exhibiting a significant ***,the matching reliability is determined by considering the relative height,slope,and ratio of the peak *** experimental results with two sets of data demonstrate that the proposed method significantly outperforms traditional approaches in terms of precision,recall,and *** experiments also establish the efficacy of the proposed method in achieving reliable matching in challenging environments characterized by repetitive and weak *** enhancement holds the potential to significantly elevate scene-matching-based navigation.

关键词： Unmanned aerial vehicle Scene matching navigation Multimodal scene matching Correlation peak Reliabilityanalysis

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi yu Jun-Li Lin Jin-han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Nonlinear empirical failure criterion for rocks under triaxial compression

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International Journal of Mining Science and Technology 2024年第3期34卷 351-369页

作者： Hongtao liu Zhou han Zijun han Zihan Chen Qinyu liu Hongkai Zhang Rongguang Zhang Linfeng Guo School of Energy&Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China China National Coal Association Beijing 100010China

Based on existing triaxial compression experimental data,a new empirical failure criterion with wide applicability was proposed considering hydrostatic pressure,second stress invariance,and maximum shear *** fitting evaluation indicators were used to verify the consistency of the new failure criterion,and the differences with the other 6 failure criteria were *** characteristics of the new failure criteria in the principal stress space were finally *** results indicate that(1)the new failure criterion exhibits strong predictive ability for triaxial experiments and has good applicability for both intact and jointed rocks;(2)the influence of hydrostatic pressure on the failure surface exhibits a non-linear trend,and different hydrostatic pressure also exhibits different distribution patterns on the deviatoric stress plane,with a distribution characteristic pattern of hexagonal snowflake-regular *** maximum shear stress has a torsional effect on the new criterion,in the three-dimensional failure *** parameters a and b of the rock have an impact on the failure surface morphology of the new criterion function on the offset surface.

关键词： surface. criterion hydrostatic

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Experimental and numerical study on ignition and combustion characteristics of boron-magnesium composite powders

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Particuology 2024年第1期84卷 12-29页

作者： Shuyuan liu Luyang han Hongmei liu Yingkai Song Linlin liu Songqi Hu Science and Technology on Combustion Internal Flow and Thermo-Structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China School of Mechanical Engineering and Rail Transit Changzhou UniversityChangzhou213164China Shanghai Institute of Space Propulsion Shanghai201112China Shanghai Engineering Research Center of Space Engine Shanghai201112China

A high-pressure laser ignition and combustion system with adjustable oxidizer gas atmosphere is established to investigate the ignition and combustion characteristics of boron-magnesium(BM)com-posite *** ignition and combustion model of BM powders is established and validated in the present *** results show that increasing water content,O_(2) content and Mg content all result in shorter ignition delay time of BM powders,among which the effect of water content is the most ***,ignition delay time increases as pressure *** combustion time decreases with increasing Mg content and ambient pressure but increases with water *** the increase of O_(2) content,combustion time of BM powders first increases and then decreases,which means a critical O_(2) content exists above which combustion time *** results show that there exists a trade-off between ignition and combustion performance of BM composite powders.

关键词： Boron magnesium powder Laser ignition Ignition and combustion model Reaction mechanism Numerical model

Clinical analysis of 12 cases of ovarian neuroendocrine carcinoma

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World Journal of Clinical Cases 2024年第6期12卷 1111-1119页

作者： Xiao-yu Xing Wei Zhang Li-Ya liu Li-Ping han Department of Gynecology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina

BACKGROUND Neuroendocrine neoplasms of the female genital tract are *** To enhance our clinical understanding of neuroendocrine carcinoma(NEC)of the *** A retrospective review was conducted on 12 patients diagnosed with NEC of the ovary,analyzing clinicopathological characteristics,treatment modalities,and survival *** The median age at diagnosis was 34.5 years(range:20 to 62 years).Among the 12 cases,9 were small cell carcinoma of the ovary and 3 were large cell *** cases were stage I tumors,one case was stage IV,and six cases were stage *** patients underwent surgery as part of their *** patients received adjuvant *** the 12 patients,one patient received radiotherapy,and one patient with a BRCA2 mutation was administered PARP inhibitor maintenance after *** median progression-free survival was 13 months,and the median overall survival was 19.5 *** cases remained disease-free,while eight cases experienced tumor recurrence,including three cases that resulted in death due to disease *** NEC of the ovary is a rare condition that is more common in women of childbearing age and is associated with aggressive behavior and poor clinical *** resection remains the mainstay of treatment,with some patients benefiting from adjuvant chemoradiation therapy.

关键词： Neuroendocrine carcinoma Ovary Pathology Treatment

Fabrication and Properties of a New Reactive Diluent for Cationic UV Curing

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1053-1060页

作者：吴正森黄笔武 liu yuansheng SHEN han School of Physics and Materials Science Nanchang UniversityNanchang 330031China

The reactive diluent prepared by siloxane modified Trimethylene oxide can improve the performance of the UV curing ***,1,7-bis[(3-ethyl-3-methoxyoxacylobutane)propyl]octadecylosiloxane(BEMOPOMTS)was synthesized from diethyl carbonate,trimethylopropanes,allyl bromide,and 1,1,3,3,5,5,7,7-octadecylosiloxane as the main raw *** can be used as reactive diluents in the field of cationic UV *** has good thermal stability,and the addition of BEMOPOMTS significantly improves the tensile strength and elongation at break of epoxy *** with the pure epoxy resin,adding 20%BEMOPOMTS increased the elastic modulus by 25%to 677 MPa.

关键词： UV curing cation curing reactive diluent siloxane

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Hyperspectral image super resolution using deep internal and self-supervised learning

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 128-141页

作者： Zhe liu Xian-Hua han Graduate School of Science and Technology for Innovation Yamaguchi UniversityYamaguchiJapan Graduate School of Artificial Intelligence and Science Rikkyo UniversityTokyoJapan

By automatically learning the priors embedded in images with powerful modelling ca-pabilities,deep learning-based algorithms have recently made considerable progress in reconstructing the high-resolution hyperspectral(HR-HS)*** previously collected large-amount of external data,these methods are intuitively realised under the full supervision of the ground-truth ***,the database construction in merging the low-resolution(LR)HS(LR-HS)and HR multispectral(MS)or RGB image research paradigm,commonly named as HSI SR,requires collecting corresponding training triplets:HR-MS(RGB),LR-HS and HR-HS image simultaneously,and often faces dif-ficulties in *** learned models with the training datasets collected simultaneously under controlled conditions may significantly degrade the HSI super-resolved perfor-mance to the real images captured under diverse *** handle the above-mentioned limitations,the authors propose to leverage the deep internal and self-supervised learning to solve the HSI SR *** authors advocate that it is possible to train a specific CNN model at test time,called as deep internal learning(DIL),by on-line preparing the training triplet samples from the observed LR-HS/HR-MS(or RGB)images and the down-sampled LR-HS ***,the number of the training triplets extracted solely from the transformed data of the observation itself is extremely few particularly for the HSI SR tasks with large spatial upscale factors,which would result in limited reconstruction *** solve this problem,the authors further exploit deep self-supervised learning(DSL)by considering the observations as the unlabelled training ***,the degradation modules inside the network were elaborated to realise the spatial and spectral down-sampling procedures for transforming the generated HR-HS estimation to the high-resolution RGB/LR-HS approximation,and then the reconstruction errors of the observations were formulated for mea

关键词： computer vision deep learning deep neural networks hyperspectral image enhancement

Sobolev Mapping of the Bergman Projections on Generalized Hartogs Triangles

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Acta Mathematica Sinica,English Series 2024年第2期40卷 451-466页

作者： Hong Yan liu Zhen han TU School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we investigate Sobolev mapping properties of the Bergman *** domain we focus on is defined byΩm/n:={(z,w)∈C^(1+N):|w1|<|z|m1/n1<1,…|wN|<|z|/m_(N)/n_(N)<1},where m=(m1,…mN)∈(Z^(+))^(N),n=(n1,…nN)∈(Z^(+))N,N∈Z^(+).Sobolev irregularity of the Bergman projections on 2 is *** also prove some Sobolev regularity results of the Bergman projections onΩm/n for m=(1,…1).

关键词： Bergman projections generalized Hartogs triangles Sobolev spaces

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Graph Signal Reconstruction from Low-Resolution Multi-Bit Observations

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Chinese Journal of Electronics 2024年第1期33卷 153-160页

作者： Zhaoting liu Chen yu Yafeng WANG Shuchen liu School of Communication Engineering Hangzhou Dianzi University

Low hardware cost and power consumption in information transmission, processing and storage is an urgent demand for many big data problems, in which the high-dimensional data often be modelled as graph *** paper considers the problem of recovering a smooth graph signal by using its low-resolution multi-bit quantized observations. The underlying problem is formulated as a regularized maximum-likelihood optimization and is solved via an expectation maximization scheme. With this scheme, the multi-bit graph signal recovery(MB-GSR) is efficiently implemented by using the quantized observations collected from random subsets of graph nodes. The simulation results show that increasing the sampling resolution to 2 or 3 bits per sample leads to a considerable performance improvement, while the energy consumption and implementation costs remain much lower compared to the implementation of high resolution sampling.

关键词： Quantization (signal) Costs Power demand Simulation Energy resolution Signal sampling Signal reconstruction